* {
    margin: 0;
    padding: 0;
}

a {
    text-decoration: none;
}

html,
body {
    width: 100%;
    height: 100%;
    background-color: #F6F6F6;
}

ul {
    list-style-type: none;
    text-align: center;
}

ul li {
    margin: 20px auto;
}

ul li a {
    font-size: 20px;
    color: #121212;
}

body {
    display: flex;
    flex-direction: column;
}

h1 {
    text-align: center;
    padding: 20px 0;
}

main {
    flex: 1;
    display: flex;
}

.left {
    width: 150px;
}

.right {
    flex: 1;
    overflow: hidden;
}

.right iframe {
    width: 100%;
    height: 100%;
    border: none;
}